There were only 15,497,240,200 EURO banknotes in circulation in June 2013 [1]. There is a study which says most go straight from the ATM to the consumer to the

There were only 15,497,240,200 EURO banknotes in circulation in June 2013 [1]. There is a study which says most go straight from the ATM to the consumer to the merchant and back to the bank. Using a big data engine, it would be very easy to trace: - Banknotes withdrawn by a person, which haven't been seen for 2 or 3 months, - Banknotes caught in drug cartel offenses and the consumer who withdrew them, - Banknotes regularly withdrawn in rich neighbourhoods and spent in poor neighbourhoods, minus direct employees of rich neighbourhoods. Banknotes deposited to a bank for the purchase of second hand cars. - As a side note, pattern changes in someone's CC spendings. A gap may mean he's aggregating money to invest on the black market. [1] https://en.m.wikipedia.org/wiki/Euro_banknotes#Circulation https://en.m.wikipedia.org/wiki/Euro_banknotes#Circulation